<root>
    <info>
        <name>华为</name>
    </info>
    <info>
        <name>ibm</name>
    </info>
</root>

<root>
    <info>
        <url>www.huawei.com</url>
    </info>
    <info>
        <url>www.ibm.com</url>
    </info>
</root>

<root>
    <info>
        <name>华为</name>
        <url>www.huawei.com</url>
    </info>
    <info>
        <name>ibm</name>
        <url>www.ibm.com</url>
    </info>
</root>

import java.io.File;
import java.io.FileOutputStream;
import java.util.List;
import org.dom4j.Document;
import org.dom4j.Element;
import org.dom4j.io.OutputFormat;
import org.dom4j.io.SAXReader;
import org.dom4j.io.XMLWriter;

public class XMLCom{
    public static void main(String[] args) {
        SAXReader reader = new SAXReader();
        File file = new File("d:\\test.xml");
        File file1 = new File("d:\\test1.xml");
        
        try {
            Document document = reader.read(file);
            Document document1 = reader.read(file1);
            
            List<Element> infos = document.selectNodes("root/info");
            List<Element> infos1 = document1.selectNodes("root/info");
            
            for(int i = 0;i < infos.size();i++){
                Element info = infos.get(i);
                Element info1 = infos1.get(i);
                List<Element> ls = info1.elements();
                
                Element add = (Element)ls.get(0).clone();
                info.add(add);
            }
            
            OutputFormat format = new OutputFormat();
            format = OutputFormat.createPrettyPrint();
            XMLWriter output = null;

            output = new XMLWriter(new FileOutputStream(new File("d://comtest.xml")), format);
            output.write(document);
            output.close();
            
        }catch(Exception e){
            e.printStackTrace();
        }
    }

}